Coding and decoding machine



Jan. 20. 1925. 1,523,689

s. HOLE CODING AND DECODING MACHINE Filed Aug. 1a. 1923 s Sheets-Shee t1 L'ZV um Him *I ,1

Jan.20,1925. 1,523,689

r s. HOLE CODING AND DECODING MACHINE Filed Aug. 18, 1923 3 Sheets-Sheet2 wlm mum mm Jan. 20. 1925. 1,523,689

$- HOLE CODING AND DECODING MACHINE .Filed Aug. 1a, 1923 3 Sheets-Sheet5 "gun NEE

llll luln I Patented Jan. 20, 1925;

um'reo STATES srn'nny HOLE, or ALBOURNE, ENGLAND.

CODING AND DECODING MACHINE.

Application filed August 18, 1923. Serial N0. 658,158:

To all whom it may concern Be it known that I, SIDNEY HOLE, a subject ofthe King of England, residing at Albourne, Hassocks, Sussex, England,have invented certain new and useful Improvements in Coding and DecodingMachines, of which the following is a specification.

This invention relates to coding and decoding machines of the typewherein one set of sign-keys is operatively connected to a second set ofsign-keysconstituting writing keys through a code-changing devicecomprising two members whereof one is moveable in relation to the otherand which has transmission points, one for each key, and operative meansis provided passipg through the said members by way of said transmissionpoints and connecting the keys in pairs, one of one set to one of theother set, and 20 the saidtransmission points of one member are arrangedall to register simultaneously with those on the other and are so spacedthat when the one member is stepped one space relatively to the othereach transmission-point of the one member will be advanced to thepreceding one of the other member, with the result that the pairs ofkeys will be changed, i. e. individual keys in one set will nowco-operate' with different keys in the other set.

Heretofore the code-changing device has provided two opposite series oftransmissionpoints between which a member moved having two other opposedseries of transmission-points, the transmission-points 0f this secondmember being irregularly cross-connected so that that point directlyopposite another was not connected to the one it was opposite but tosome other point. This central member therefore constituted the meansfor giving an initial setting-up of a code in that a key of one setwould thereby be made to operatea key which was not apparently thecorresponding key in the other set, and further codechanging waseffected by stepping the one member relatively to the other. To changethis initial setting-up of the code required the substitution of anothermember provided with the necesparatusis worked electrically the samemem-'ber could be rc-W1red,either of which operasariy; cross-connections; orwhere the aptions however would absorb an undesira'blo amount of time.

The object of the present invention is to provide a form of codechanging device whereby the amount of time necessary for setting-upwhere a change is required may be greatly reduced. 7

According to the present invention coding or de-coding apparatus of thetype described is characterised by the operative connections between onesetof keys and one member providing the transmission-points being of aflexible character, such as rubber tubes, and provided with engagingmeans, such as plugs, adapted to be instantly-engaged each faces of theplates and afford a hold for the engaging-means-of the connections withthe keys on the outer faces. One of the plates or discs 'is convenientlymade stationary and the other arranged to move or rotate upon it.

Preferably, pneumatic means is employed for operating that set of keyswhich is not manually operated; such means comprising "I-lXGS controlledby the manually-operated keys, tubes extending from these valves to oneseries of transmission-points on one of the members of the code-changingdevice, fluid-operated pistons connected one toeach of the keys of theother set, and tubes extending from the cylinders of these pistons tothe other set of transmission-points, the aforesaid valves beingarranged to control the action of the working-fluid in such manner thatwhen any one valve is opened by the manual depression of one key a keyof the other set will be operated by the fluid.

Both sets of keys may be arranged to impress signs upon a paper sheet orother receiver, in which case each set of keys is provided withself-operating means, one connection only extends from each key to thecode-changing device, and changin -0ver means is provided so that eitherset 0 keys can at will becorne the manually-operated set and the otherset the responsivelyoperated set.

Two standard typewriters may be employed having the keys of oneoperatively connected to the keys of the other through the code-changingdevice; such an arrangement avoids unnecessary expense in providingspecial means for recording the operations of the keys and thusconsiderably reduces the cost of producing a machine in which either ofthe two sets of keys can be used at evill for coding or decoding. 1

In the accompanying drawings which il lustrate one method of carryingout this invention Figure 1 shows diagrammatically the generalarrangement of the machine;

Figure 2 is a side elevation of the codechanging device on a. largerscale than that of Figure l;

Figure 3 is a central vertical section through the code-changing deviceon the line 3-3 of Figure 2;

Figure 4 is. a side elevation of one of the designation plates used inthe machine;

Figure 5 is a front elevation showing the arrangement of the valve-boxeswhereby one set of keys is operated from another;

Figure 6 is a plan of the parts shownin Figure 5, and

Figure 7 is a vertical section through the parts shown in Figure 5 onthe line 77 of that figure.

Like reference letters indicate like parts throughout the drawings.

The machine shown in the drawings comprises two standard typewriters Aand B respectively, which are provided with the usual keys A B wherebytypewritten matter can be executed.

Beneath the typewriters are three or more valve-boxes C, D respectively,the valves ,in which are operatively connected with the keys ashereinafter described.

Between the two typewgiters is a code-. changing device comprising afixed disc and a movable disc E which parts will hereinafter bedescribed in greater detail.

Extending from the valve-boxes C are a number of tubes F, whereof onlyone is shown in Figure 1, one tube being allotted to the valve of eachtype-key, and .having connection at the end remote from thetypewriterwith the plate E of the code-chang5 ing device. Similarly, thevalve-boxes have a series of tubes F connecting the valves therein withthe disc E of the codechanging device, and these tubes are broughtopposite one another by the codehanging device so that when one of the:eys B is manually-operated a key A will be operated by pneumatic meansor vice versa.

Exhaust apparatus is connected to the chamber G and thence by a conduitG and branch-conduits G G to the valve-boxes The disc E is carried fromthe baseboard H by a bracket E and is provided with a series of holes Earranged in a circle, each carrying a nipple E to receive one of thetubes F. Similarly, theplatc E is provided with a series oftapered holesE which are arranged to register with the holes E all the holes beingequally spaced. The plate E has on its'periphery a. series of teeth Eone allotted to each hole, and

these teeth are engaged by a retaining'pawl J carried on a standard J bya'pivot-pin" J The pawl has on it two fiats J J 4 respectively and aspring J 5 bears against one or other of these flats according to theposi-' tion in which the pawl lies. A spiral spring E is mounted in arecess of the disc E and tends always to rotate the disc in a directionto engage the pawl J. It thus follows that if the disc is advanced oneor more teeth it will be retained in the position to which it isadvanced by the pawl J, and the spacing of the teeth is such thatwhatever tooth is engaged by the pawl J the holes E ,'E will be inregister with each other.

A series of hollow tapered plugs F are secured to the ends of the tubesF and serve as engaging-means between these tubes and the holes E in theplate E Each plug F has a flat F thereon, and on this is marked the si11 corresponding to the sign of the key to which that tube F isallotted.

The holes E E thus constitute transmission-points which communicate witheach other on the inner faces of the, plates. Also the holes afford ahold for-the engaging means, viz: the plugs F and nlpples E of theconnections with thekeys on the outer 11 faces of the plates E, E

To step the disc E round, a code-changing key K is provided. This ismounted to slide vertically in-a support K and is nor-- mally retainedin the raised position by a spring K which .carries a pawl K When thekey is in the raised position the pawl lies against a pin K' on a fixedmember, and is held back thereby against the action of its spring K sothat it lies clear of the teeth E of the disc, but as the key isdepressed the pawl moves towards the disc and engages the tooth whichlies immediately beneath it. Continued depression of the key will thenmove the disc around the space equal to one tooth allowing theretainingpawl J to drop behind its next tooth, where-- upon the key Kcan be released and will again resume thg position shown in Figure 2.

The disc E carries a stop J which cooperates with a pinJon the pawl J.When the disc is in the zero position the stop is slightly'in advance ofthe pin J as shown in Figure 2, and it will travel further there.- fromas the disc is advanced until the latter has completed one revolution,when the stop J 6 will be brought against the underside ofthe pin J Thiswill lift the pawl so that it will spring back to the position shown inchain-line in Figure '2 with the flat J 3 engaged by the spring J andthen as the key Krises after the last operation the disc will fly backto the zero position under the action of its'spring E, and on reachingthe zero position the stop J 6 will strike the pin J 7 and bring thepawl again into engagement so that the parts resume the position shownin Figure 2. g

In order that the tubes F, F may be easily designated irrespectively ofthe plugs F (which moreover are only shown as ems loyed with the tubes Fthough they may be also used with the tubes F if desired) the tubes arepassed through designationplates L. These plates are supported incarriers L so that they can be turned therein if desired, and they areprovided with a series of holes through which the tubes are. threaded,each hole havingset against it the sign of the key to which that tube isallotted.

All the valve-boxes C and D are in every respect alike and therefore apart of one valve-box C need only be described in detail.

In Figures 5 and 7 part of a tvne-key B is shown, which key is connectedby a link B to the rod of a piston C The piston is conveniently ofgraphite and slides in a cylinder or barrel C formed for it in thevalve-box. The piston-rod extends beyond the cylinder so that it crossesa transverse passage C which communicates with a longitudinal passage C;This lower extension of the piston-rod has in it an annular port C whichregisters with the passage C when the key B is in the depressedposition. A tubular hand-operated valve M is arranged to slidevertically in the valve-box and extends below the same to receive one ofthe tubes F. This valve M is plugged at the upper end and has a lateralport M which communicates by a passage M with the cylinder C when thevalve is in the raised position shown in Figure 5. The valve can beraised and lowered by a sliding-bar M whichis slotted to receive a pin Mon the lower end of the valve, and when the valve is in the loweredposition its port M registers with the transverse passage C Eachvalve-box is made of the same length electricallydriven exhaust-pump.this it will be seen that the conduits G G as a row of keys and containsas many cylinders as there are keys, each key being connected with apiston operating in a cylinder located beneath it. The passage C runsfrom one end of the valve-box to the other three tubes N connected inthe same manner to the conduit G Thebars l\ 3 are provided withcam-slots M which engage pins M on a fixed part of the machine and,consequently, when the bars are slid in one direction, the valves M areall raised, as shown in Figures 5 and 7, but when the bars are moved inthe other direction, that is from left to right of Figure 5, they willdraw all the valves M down to their'second position. i

The operationof this machine is as follows:

'lf he working-fluid emplbyed is the external air at atmosphericpressure, this being rendered operative by maintaining a partial vacuumon the container G through any convenient exhausting-means, such as an GM and N, and the longitudinal passages C and. their companion passagesin the valve-boxes D will always be maintained under partial vacuum.

Supposing, therefore, it is desired to n1au ually operate the keys B ofthe typewriter B and produce responsive operations of the keys A of thetypewriter A, the bars M" of the valve-boxes C will be moved in suchdirection as to bring all the manually-operated valves M to their loweroperative position, that is with the ports M in register with thelateral passages C, but the bars M of the valve-boxes D will be left inthe position shown in Figures 5 and 7 so that the ports M ofthe'hand-operated valves M will register with the passages M of thecylinders in the valve-boxes D. It therefore follows that when a key'Bis depressed the annular port C of the corresponding pistonrod will bebrought to register with the passage C and, consequently, the tube Fcorresponding to that key will be put under partial vacuum through theport M of its valve M being thrown into communication with thelongitudinal passage C through the transverse passage C This tube F is.however, operatively connected with one of the tubes F through thecode-changing device E, E and therefore the cylinder in the valve-boxcorresponding to that tube F From III)

will be put under vacuum with the result that its piston will be forceddown by atmospheric pressure, and the type-key A connected thereto willthus be responsively operated through the manual operation of thetype-key B Preferably, the code-changing device E, E has an initial codeset-up therein, that is to say the tube F corresponding to the key A inthe B typewriter does not register with the tube F corresponding to thekey A in the A typewriter, and so forth, but the tubes are arrangedaccording to some initial code relatively to one another. The

- tubes F could be arranged, for example, in

alphabetical order and thetubes F plugged intothe holes of the plate Ein av mixed order so that when the key A was struck on the B machine akey, for example N, might be struck on the A machine, and so forth.

It is desirable to vary this initial code at times and for this purposethe plugs F are of great advantage as they afford an engaging-meansbetween the tubes and the codechanging device which can be instantlyengaged with or disengaged from any one'of the transmission-pointsrepresented by the holes E in the code-changing device.

After a given number of operations of the -keys, decided upon byarrangement, the

code-changing key K is operated. This may be operated once or twice, ora varying number of times according to arrangement, so that the initialcode is changed either at the end of each line or after the completionof each word, or after so many letters have been written.

From the above description it will be seen that a message can be writtenon the typewriter B and will appear in the ordinary form on paper put inthat typewriter, but simultaneously. the same message will be coded bythe machine A so that an apparently meaningless arrangement of signsappears on the paper-sheet in-that typewriter, To de-code this messagethe bars M of the two sets of manually-operated valves M are reversed sothat the typewriter A is now the manually-operated one and thetypewriter B becomes the responsively-operated one, when by startingwith the initial code as originally arranged and the coding disc E,

E in the same position as it was when the coding was started (presumablyat zero) and operating the code-changing device at the same intervals asit was operated when coding the message, a de-coded message will bewritten on the typewriter B which in every respect corresponds to themessage previously written thereon when coding it.

It will be seen that by reason of being able to change the code.continuously by merely operating the key K, and also to change-,theinitial code by re-arranging the plugs F an endless number of changescan be produced whichrenders de-coding by ordinary rules impossiblebecause there need never be a sufficientnumber of letters written in anone code to afford a key to the code. It has been found in practice thatthe plugs F can all be removed and replaced according to any new code infive minutes or less.

Obviously, both plates E, E may rotate if desired, for example theycould rotate in opposite directions being operated by tlie same orseparate keys, or they could rotate in the same direction and bearranged to be operated by separate keys; also plugs similar to theplugs I. could be provided in the plate E so that these could be changedas well as those in the plate E for setting-up any initial code.

Obviously, the plates need not rotate relatively to one another, as solong as one plate moves over the other the desired changing of code canbe effected, for instance, one plate could be made to slide horizontallyrelatively to the other and stepped by a suitably arranged key and pawl.

By providing the spring return to zero the operator does not have toconsider whether he has carried the plate round one cycle or not as itwill automatically return to zero at the end of the cycle and hecontinues to operate the key K according to the prearranged programme.

I claim 1. In a machine of, the. character described, the combinationwith a set of character-producing sign-keys, a second set of sign-keyswhich is a duplicate of the first set, a code-changing device comprisingtwo code-changing members whereof one is movablein relation to theother, said members having each a plurality of transmission points, onefor each key of a said set of signkeys, which points of one member arearranged to register with those on the other and are so spaced that whenthe one member is stepped one space relatively to the other eachtransmission point of one member will be advanced to the preceding .oneof the other member, means interconnecting the sign-keys of one of saidsets each with one of the transmission points of one of saidcode-changing members, and a plurality of flexible connecting membersoperatively connecting the sign-keys of the other set each at will withany one of the transmission points of the other of said code-changingmembers so as to be readily attachable to and detachable from thelatter, substantially as described.

2. In a machine of the character described, the combination with aset ofcharacter-producing sign-keys, a second set of sign-keys which is aduplicate of the first set, a code-changlng device comprising twocode-changing members I whereof one is movable in"'relation to theother, said members having each a plurality of transmission points, onefor each key of a said set of sign-keys, which points of one member arearranged to register with those on the other and are so spaced that whenthe one member is steppedone space relatively to the other eachtransmission point of one member will be advanced to the preceding oneof the other member, tubes operatively. connecting the sign-keys of oneof said sets each with one of the transmission points of one of saidcode-changing members, and a plurality of rubber tubes operativelyconnecting the sign-keys of the other set each at will with any one ofthe transmission points of the other of said code-changing members so asto be readily attachable to and detachable from the latter,substantially as described.

3. In a machine -of the character described, the combination with a setof character-producing sign-keys, a second set of sign-keys which isaduplicate of the first set, a code-changing device comprising twocode-changing members whereof one is movable in relation to the other,said members having each a plurality of transmission.

points, one for each key of a set of signkeys, which points of onemember are arranged to register with those on the other and are sospaced'that when the one member is stepped one space relatively to theother each transmission point of one member will be advanced to thepreceding one of the other member, means interconnecting the sign-keysof one of said sets each with one of the transmission points of one ofsaid codechanging members, a plurality of engaging means, one for eachtransmission point ofthe other of sald code-changmgmembers, adaptrd tobe engaged each with, and disengaged from any one of the transmissionpoints in that member, and a plurality of flexible connecting membersoperatively connecting the sign-keys of the other set each with one saidengaging means; substantially'as described.

-:1 In a machine of the character described, the combination with a setof" character-producing sign-keys, a second set of sign-keys which is aduplicate of the first set, a code-changing device comprising twocode-changing members whereof one is movable in relation to the other,said membershave each a plurality of transmission points, one for eachkey of a setof sign- .Ikeys, which points of one member are arranged toregister with those on the other and are so spaced that when the onemember is stepped one space relativelyto the other each transmission)oint of oneimember will be advanced to tie preceding one of the other.member, means interconnectin the sign-keys of one of said sets each witone of the transmission points of one of said code-changing members, aplurality of plugs,

one for each transmission point in the form of a hole, in the other ofsaid code-changing members, which plugs are readily placeable into andremovable from any one of the transmission'holes in that member, and aplurality of flexible connecting members operatively connecting thesign-keys of the other set each with one of said plugs, sub-- stantiallyas described.

5. In a machine of the character described, the combination with aset'of character-producing sign-keys, a second .set' of characterproducing sign-keys which is a duplicate of the first set, of only onecodechanging device comprising two codechanging members whereof one ismovable in relation to the other, said members having each a pluralityof transmission points, one for each key of a set-of sign-keys, which"oints of one member are arranged to register with those of the other andare so spaced that when one member is stepped one space relatively tothe other each transmission point of one member is advanced to thepreceding one of the other member, two sets of' automatic key-operatingdevices, one device for each key in set thereof each with one .of thetrans- I mission points of one of said code-changing members, and thesecond of said groups of connectin members connects the key-operatingdevlces of the second set thereof each with one of the transmissionpoints of the second code-changing member, and two sets of change-overmechanisms, one set associ ated with each set of key-operating devi es,and each set so arranged as in one position to render its associatedkey-operating devices inoperative, and to make the key-operating devicesof the other set of keys controllable by a manual operation of the keysassociated with the first set of change-over mechanism, and in anotherposition to render its associated key-operating devices controllable bymanua-Lpperation of the keys associated with the second set ofchange-over mechanism, substantially as described,

6. In a machine of the character described, the combination of a set ofcharacter-producing sign-keys, a secondset of character-producinsign-keys which is a duplicate of the v rst set, only' one codechangingdevice comprising two codechanging members whereof one is movable inrelation to t c other, said members having each a plurality oftransmission points, one for each key of a set of sign-keys, whichpoints of one member are arranged to register with those of the otherand are so spaced that when one member is stepped one spaced relativelyto the other each transmission point of one member is advanced to thepreceding one of the other member; two sets of automatic key-operatingdevices, one device for each key in each set of keys, for actuating thesign= keys for producing characters a pluralityof power-supply means, atleast one allotted to each set of key-operating devices; controllingmeans comprising only one set of connecting members arranged in twogroups associated each with a set of sign-keys, one member allotted toeach key-operating device, one of which groups of connecting membersconnects the key-operating devices of one set thereof each with one ofthe transmission points of one of said-codechanging members, and thesecond of said groups of connecting members connects the key-operatingdevices of the second set thereof each with one of the transmissionpoints of the second code-changing member, and two sets of key-operatedswitch mechanisms, each mechanism being associated with one of said setsof key-operating devices, and each mechanism being adapted, when itsallotted key is depressed, to oper atively connect one of said powersupply means to one of said connecting members; and two change-overswitch mechanisms, associated each with one of said sets ofkeyoperat-ing devices, and each operated independently of the sign-keysfor rendering the said key-operated switch mechanisms inoperative, whichchange-over switch mechanlsms are arranged each operatively to connect aconnecting member with a respective key-operating device, substantiallyas described.

7. In a machine of the character described, the combination with a setof character-producing sign-keys, and a second set ofcharacter-producing sign-keys which is a duplicate of the first set, ofonly one codechanging device comprising two code-changing memberswhereof one is movable in relation to the other, said members havingeach a plurality of transmission points, one

for each key of'a set of sign-keys, which oints'of one member arearranged to reg ister with those of the other and are so spaced thatwhen one member is stepped'one space relatively to the other eachtransmission point of one member is advanced to the preceding one of theother member, two sets of automatic pneumatic key-operating -devices,one device for each key, for actuating the sign-keys for producingcharacters; pneumatic controlling means for controlling theself-operation of the devices of one set from the devices'of the secondset, and those of the second set from those of the first set, whichcontrolling means comprise only one set of connecting members in theform of tubes arranged in two groups associated each with a set ofsign-keys, one tube allotted to .each key-operating device, one of whichgroups of tubes connects the key-operating devices of one set thereofreadily detachably each with one of the transmission points of one ofsaid code-changing members, and the other of said groups of tubesconnects the key-operating devices of the second set thereof readilydetachably each with one of the transmission points ofthe secondcode-changing member; and two sets of change-over mechanisms, one setassociated with each set of key-operating devices, and each set soarranged as, in one position to render its associated key-operating'devices inoperative, and to make the keyoperating devices of the otherset of keys controllable by a manual operation of the keys associatedwith the first set of change over mechanism, and in" another position torenden its associated key-operating devices controllable by manualoperation of'the keys associated with the second set of changeovermechanism,substantially as described.

8. In a machine of the character described, the combination of a set ofcharacter-producing sign-keys, a second set of character-producingsign-keys which is a duplicate of the first set, only one code-changingdevice comprising two code-changing members whereof one is movable inrelation to the other, said members having each a plurality oftransmission points in the form of ports, each having a hollow plug, oneplug for each. keyof a set of sign-keys, which v ports of one member arearranged to register with those of the other and are so spaced that whenone member is stepped one space relatively to the other each port ofonen1ember is advanced to the preceding one of the other member; twosets of automatic pneumatic key-operating devices; one device for eachkey, for actuating the sign-keys for producing characters, a pluralityof power ducts, at least one allotted to each set of, key-operatingdevices; controlling means comprising only one set of tubes arranged intwo groups associated each with a set of sign-keys, one tube allote'd'to each keyoperating device, one of which groups of tubesreadilydetachably connects the keyoperating devices of one set thereof eachwith one of the said plugs of one of said code-changing members, and thesecond group-connects the key-operating devices of the second setthereof each with one of the plugs of .the secondcode changing member,

and two sets of key-operating switch mechanisms, each mechanism beingassociated with one of said sets of key-operating devices, eachmechanism being adapted, when its allotted key is depressed, tooperatively connect one of saidpower ducts to one "of said tubes; andtwo change-over switch mechanisms, associated each with one of said setsof key-operating devices, and each operated independently of thesign-keys, for rendering the said key-operated switch mechanismsinoperative, which change-over switch mechanisms are arranged eachoperatively to connect a connecting member with a respective keyoperating device, substantially as described.

9. In a machine of the character described, the combination with a setof character-producing sign-keys, and a second set ofcharacter-producing sign-keys which is a duplicate ofthe first set, ofonly one codechanging device comprising two code-changing members in theform of plates arranged face to face, whereof one is movable in relationto the other, said plates having each a plurality of transmission pointsin the form v of ports, one for each key of a set of signkeys, whichports of one plate are arranged to register with those of the other andare so spaced that when one plate is stepped one space relatively to theother each port of one plate is advanced to the preceding one of theother plate; two sets of automatic pneumat c key-operating devices, one.

device for each key, for actuating the signkeys for producingcharacters; pneumatic controlling means for controlling theselfoperation of the devices of either set from the devices of the otherset, which controlling means comprise only one set of connecting membersin the form of tubes arranged in two groups associated each with a setof sign-keys, one. tube allotted to each key-operating device, one ofwhich groups of tubes connects the key-operating devices of one setthereof each with one of the ports of one of said plates, and the secondof said groups of tubes connects the key-operating devices of the secondset thereof each with one of the ports of the second plate; and two setsof change-over mechanisms,one set associated with each set ofkey-operating devices, and each set so arranged as, in one position torender its associated key-operating devices inoperative, and to makethekey-operating devices of the otheriset of keys controllable by amanual operat on of the keys associated with the first set ofchange-over mechanism, and in another posit on to render its associatedkeyoperating devices controllable-by manual operationof the, keysassociated with the second set of change-over.mechanism, substantiallyas de-- scribed. i r -lO. In a machine of the character decribed, thecombination with a set of character-producing sign-keys, and a secondset of character-producing sign-keys which is a duplicate of the firstset, of only one codechanging device comprising two code-changingmembers in the form of plates arranged face to face, whereof one isrotatable over the other, said members having each a plurality oftransmission points in the form of ports, one for each key of a set ofsign-keys, which ports of one member are arranged to register with thoseof the other and are so spaced that when one member is stepped one spacerelatively to the other each port of one member is advanced to thepreceding one of the other member; two sets of automatic pneumatickey-operating devices, one device for each key, for actuating thesignkeys for producing characters; pneumatic controlling means forcontrolling the selfoperation of the said devices of either set from thedevices of the other set, which controlling means comprise only one setof connecting members in the form of tubes arranged, in only two groupsassociated each with a set of sign keys, one tube allotted to eachkey-operating device, one of which groups of tubes connects thekey-operating devices of one set thereof each with one of the ports ofone of said code-changing members, and the second of said groups oftubes connects the key-operating devices of the second set thereof eachwith one of the ports of the second codechanging member; and two setsof'changeover mechanisms, one set associated with each set ofkey'operating devices, and each set so arranged as, in one position torender its associated key-operating device inoperative, and to make thekey-operating devices of the other set of keys controllable by a manualoperation of the keys associated with the first set of change-overmechanism. and in anothei. position to render its associatedkey-operating devices controllable by manual operation of the keysassociated with the second set of change-over mechanism, substantiallyas described.

11. In a machine'of the character do scribed, the combination of a setof manually-operable sign-keys, and l a set of character-producingsign-keys which is .a duplicate of the first set; a code-changing devicecomprising two code-changing members whereof one is'movable in relationto the other, said members having each a plurality'of transmissionpoints one for each key of a set of sign-keys, which points of onemember are arranged to register with those of the other and are sospaced that when the one member is stepped one space relatively to theother each transmission point of one member will be advanced to thepreceding one of the other member; pneumatic means connecting the twosets of keys together by way of the said codechanging device, saidpneumatic means comprising; valves controlled by the manually operablekeys, one valve for each key; a set of tubes extending one from eachvalve to the transmission points of one of said code changing members;cylinders allotted one to each character-producing key; pistons, one ineach cylinder, connected each to a character-producing key; a second setof tubes extending one from each cylinder to the transmission points ofthe other of said code-changing members; and means for establishing adifference of pressure at the two sides of said pistons, connected tosaid first set of tubes by way of said valves, whereby when any onevalve is opened by the depression of one manually-operable key, acharacter-producing key will 'be operated by the fluid pressure actingon its allotted piston, substantially as described.

12. In a machine of the character described, the combination with a setof manually-operable sign-keys, and a set of character-producingsign-keys which is a duplicate of the first set, of a code-changingdevice comprising two code-changing members whereof one is movable inrelation to the other, said members having each a lurality oftransmission points in the of holes, one-for each key of a set ofsignkeys, which holes of one member are arranged to register with thoseof the other and are so spaced that when the one member is stepped onespace relatively to the other each hole of one member will be advancedto the preceding one of the other member; pneumatic means connecting thetwo sets of keys'together by way of the said codechanging device, saidpneumatic means com prising valves controlled by the manuallyoperablekeys, one valve for each key, a set of tubes extending one from eachvalve to the holes of one of said code-changing members, cylindersallotted oneto each charac ter-producing key, pistons, one in eachcylinder, connected each to a characterproducin key, a second set oftubes extending one om each cylinder to the holes of the other of saidcode-changing members, and tubularplugging means, detachably insertedone in each code-changing member, connected each to one of said tubes;and means for establishing a difference of pres-- sure at the two sidesof said pistons, connected to said first set of tubes by way of saidvalves, whereby when any one valveis opened by the depression of onemanuallyoperable key, -a character-producing key will be operated by thefluid pressure acting on its allotted piston, substantially asdescribed.

18, In a machine of the character described, the combination of a set ofmanually-operable sign-keys, and a set of orm character-producingsign-keys which isa duplicate of the first set; a code-changing devicecomprising two code-changing mem bers whereof one is movable in relationto the other, said members having each a plurality of transinissionpoints one for each key of a set of sign-keys, which points of onememberare arranged to register with those of the other and are so spacedthat when the one member is stepped one space relatively to the othereach transmission point of one member will'be advanced to the precedingone of the other member; pneumatic means connecting the two sets of keystogether by way of the said codechanging device, said pneumatic meanscomprising valves controlled by the manuallyoperable keys, one valve foreach key, .a

.set of tubes extending one for each Valve to the transmission points ofone of said codechanging members, cylinders allotted one to .eachcharacter-producing key, pistons, one in each cylinder, connected eachto a character-producing key, and a second set of tubes extending onefrom each cylinder to the transmission points of the other of saidcode-changing members; a support, a

plate mounted to rotate on said support about an axis extendingtransversely through the plate, which plate has a plurality ofperforations; one for each tube of one of said sets of tubes, throughwhich the same are threaded, which perforations are marked each with asign corresponding to the key to which the tube extending through it isallotted; and means for establishing a difference of pressure at the twosides of said pistons, connected to said first set of tubes by way ofsaid valves, whereby when any one valve is opened by the depression ofone manually-operable key, a characterproducing key will be operated bythe fluid pressure acting on its allotted piston, substantiallyasdescribed.

14:. a machine of the character described, the combination of a set ofcharacter-producing sign-keys, and a second set of sign keys which is aduplicate of the first set; a code-changing device comprising two platesplaced face to face whereof one 1s movable over-the other, said plateshaving each a plurality of transmission points, one for each key of aset of sign keys, which points of one plate are arranged to communicateeach with a point at the inner face of the other plate and are so spacedthat when the one plate is stepped one space relatively to the othereach transmission point of one plate will 'be advanced to the pre-'ceding one of the other plate; the movable plate having on its peripheryteeth spaced apart to correspond to the stepping required forsingle-step changes of-thev transmission points, a key arranged toengage said teeth in succession and advance the movable plate the outerface thereof so as to be readily attachable to and detachable from thelatter, substantially as described.

15. In a machine of the'character described, the combination of a set ofcharacter-producing sign-keys, and a second set of sign-keys which is aduplicate of the first set; a code-changing device comprising two platesplaced face to face whereof one is movable over the other, saidplateshaving each aplurality of transmission points, one for each key ofa set of sign-keys, which points of one plate are arranged tocommunicate each with a point at the inner face of the other plate andare so spaced that when'the one plate is stepped one space relatively tothe other each transmission point of one plate will be advanced to-thepreceding one of the other plate; the movaible plate having on itsperiphery teeth spaced apartto correspond to the stepping required forsingle-step changes of the transmission points, a key arranged to engagesaid teeth in succession and advancethe movable plate one space at atime, a spring tending to move the movable plate in a direction oppositeto that in which it is advanced by the key, and a locking pawl forpreventing the'return movement of the movable plate after each advance;means detachably interconnecting the sign-keys of one of said sets eachwith one of the transmission points of one of said plates at the outerface thereof, and a plurality of flexible connecting members sooperatively connecting the sign-keys of the other set each with one ofthe transmission points of the other a,

plate at the outer face thereof, as to be readily attachable to anddetachable fromv the latter, substantially as described.

16. In a machine of the character described, the combination with a setof manually-operable sign-keys, character-producing mechanism arrangedto be actuated by said keys, a second set of manually-operable signkeyswhich is a duplicate of the first set, character-producing mechanismarranged to be actuated [by said second set of keys, and transmissionmeans operatively interconnecting the two sets of keys and arranged toautomatically actuate a key of one set when a key of the other set ismanually depressed, said transmission means including;-

a code-changing-device comprising two codein relation to the other, saidmembers having each a plurality of transmission points, one for each keyof a set of sign-keys, which points of one member are arranged toregister with those on the other and are so spaced that when the onemember is stepped one space relatively to the other, each transmissionpoint of one member will be adanced to the preceding one of the othermember; two sets of key-actuating devices allotted one to each set ofkeys; two sets of power-transmission means included in said transmissionmeans interconnecting each one of said sets of key-actuating deviceswith the transmission po nts of one of said codechanging members so asto be detachable from the latter, one connection only extend-- ing fromeach key-actuating device to.its allotted member; and two change-overdevices, one allotted to each set of keys, for enabling each key of aset alternatively to control the transmission of power to, and to becontrolled by the transmission of power from a key of the other set byway of said code-changing device, substantially" as described.

17. In a machine of the character described, the combination witlra setof manually-operable sign-keys, character-producing mechanism arrangedto be actuated by said keys, a second set of mahually-operable sign-keyswhich is a. duplicate of the first set, character-producing mechanismarranged to be actuated by said second set of keys, and pneumatictransmission means operatively interconnecting the two sets of keys andarranged to automatically actuate a key of one set when a key of theother set is manually depressed, said transmission means including acode-changing device comprising two code-changing members whereof one ismovable in relation to the other, said members having each a pluralit oftransmission points. one for each key 0 a set of sign-keys, which pointsof one member are arranged to register with those on the other and. areso spaced that when the one member is stepped one space relatively tothe other, each transmission point of one member will be ad vanced tothe preceding one of the other member, .two sets of key-actuatingdevices allotted one to each set of keys, each set of'key-actuatingdevices comprising cylinders, one for each key, a piston 1n each cyl--inder operatively connected to its allotted.

key, each cylinder having a duct for connection to a tube,'and afluid-supply passage leading to said duct, a valve associated with eachpiston for controlling the fluid-supply passage of its allottedcylinder, and each changing members whereof one is movable thetransmission points of said code-changing members so as to be detachablefrom the latter, one tube only extending from each key-actuating deviceto its allotted member, and manually operable change-over devices, atleast one allotted to each set of keys, for

reversing said change-over valves, substantially as described.

18. In a machine of the character described, the combination with a setof manually operable sign-keys, character-producing mechanism arrangedto be actuated by said keys, a second set of manually operable signkeyswhich is a duplicate of the first set, character-producing mechanismarranged to be actuated by said'second set of keys, and pneumatictransmission means operatively inter-connecting the two sets of keys andarranged to automatically actuate a key of one set when a key'of theother set is manually depressed, said transmission means including acode-changing device'comprising two codechanging members whereof one ismovable in relation to the other, said members having each a pluralityof transmission points, one for each key of a set of sign-keys, whichpoints of one member are arranged to register with those on the otherand are so spaced that when the one member is stepped one spacerelatively tothe other, each transmission point of one member will beadvanced to the preceding one of the other member, two sets of keyactuating devices allotted one to each set of keys, each set ofkeyactuating devices comprising cylinders, one for each key, a piston ineach cylinder operatively connected to its allotted key, each cylinderhaving a duct for connection to a tube, and a transverse fluid-supplypassage leading to said duct, each piston carrying a valve forcontrolling the fluid-supply passage of its allotted cylinder, and eachcylinder having a change-over valve for connecting said duct either toits cylinder or to said fluid-supply passage; two sets of tubes 1connecting each one of said ducts with one of the transmission points ofsaid codechang-ing members so as to be detachable from the latter, onetube only extending from each ke -actuating device to its allottedmember, nd manually operable changeover devices, one allotted to eachset of keys, for reversing said change-over valves, substantially asdescribed. 19. In a machine of the character described, the combinationwith a set of manually-operable sign-keys, arranged in rows,character-producing mechanism arranged to be actuated by said keys, asecond set of manually-operable sign-keys arranged in rows which isaduplicate of the first set, character-producin mechanism arranged to beactuated by sai second set of keys, and pneumatic transmission meahsoperatively interconnecting the two sets of keys and arranged toautomatically actuate a key of one .keys, which points of one member arearranged to register with those of the other and are so spaced that whenthe one memher is stepped one space relatively to the other, eachtransmission point ofone member will be advanced to the preceding one ofthe other member, two sets of key-actuating devices allotted one to eachset of keys, each set of key-actuating devices comprising cylinders, onefor each key, a piston in each cylinder operatively connected to itsallotted key, each cylinder having ,5 a duct for connection to a tube,and a transverse fluidsnpply passage leading to said duct, each pisioncai rying a valve for controlling the fluid-sup 'ily passage of itsallotted cylinder, and each cylinder having a change-over valve forconnecting said duct either to its cylinder or to said fluid-supplypassage, each change-over valve being of tubular form closed at one endand having a side port and movable endwise to bring it to two operativepositions, which tubular valves are arranged in rows corresponding tothe rows of keys; two sets oftubes connecting each one of said duetswith one of the transmission points of said code-changing member so astobe detachable from, the latter, one tube only extending from eachkey-actuatin device to its allotted member, and manually-operablesliding'cam-members, one for each row of keys in each set, for actuatingsaid changeover valves, substantially as described.

20.1n a machirie of the character described, the combination with atypewritingmachine having a set of character-producing sign-keys,asecond typewriting-machine having a set of sign-keys which is aduplicate of the first set, a code-changing device comprising only twocode-changing members whereof one is movable in relation to the other,said members having each a plurality of transmission points, one foreach key of a said set of sign-keys, which points of one member arearranged to register with those on theother and are so spaced that whenthe one member is stepped one space relatively to the other eachtransmission point of one member will be advanced to the preceding oneof the other member, means interconnecting the sign-keys of one of saidmachines each with one of the transmission points of one ofvsaid codechanging members, and a plurality of flexible connecting membersinterchangeably connecting the sign-keys of the other machine with thetransmission points of the other of said 21. In a machine of thecharacter de scribed, a code-changing device comprising only twocoaxialdiscs placed face to face, whereof at least one is rotatable overthe other, said discs having each aplurality of transmission pointsadapted for detachable connection each to a transmission member allottedto a sign-key, which points of one disc are arranged to communicate eachwith a point at the inner face of the other disc and are so spaced thatwhen one disc is rotated relatively to the other each transmission pointofone disc will be advanced to the preceding one of the other disc,substantially as described.

22. In a machine of the character described, a code-changing devicecomprising only two coaxial discs placed-face to face, whereof one isrotatable over the other, said discs having each a plurality oftransmission points adapted for detachable connection each'to atransmission member allotted to a sign-key, which points of one. discare arranged to communicate each with a point at the inner face of theother disc and are so spaced that when one disc is rotated relativelytothe other each transmission point of one disc will be' advanced to thepreceding one of the otl1er disc,'the movable disc having on itsperiphery teeth spaced apart to correspond to the stepping required forsingle step changes of the transmission points, a key arranged to engagesaid teeth insuccession and advance the movable disc one space at atime, and means for arresting the movable disc in the position to whichit is advanced, substantially as described.

23. In a machine of the character described, a code-changing devicecomprising two coaxial discs placed face to face, whereof one isrotatable over the other, said d scs having each a plurality oftransmission points for detachable connection each to a transmissionmember allotted to a sign-key, which points of one disc are arrangedtocommunicate each with a point at the inner face of the other disc andare so spaced that when one disc is rotated relatively to the other,each transmission point of one disc will be advanced to the precedingone of the other disc, the movable disc having on its periphery teethspaced apart to correspond to the stepping required for singlestepchanges of the transmission po nts, a key arranged to enga e said teethin succession and advance t e movable disc one space at a time, a springtending to move the movable disc in a direction opposite to that inwhich it is advanced by the key, and a locking pawl for preventing thereturn movement of the movable disc after each advance, substantially asdescribed.

24. In a' machine of the character described, a code-changing devicecomprising two coaxial discs placed face to face, Whereof one is fixedand the other is rotatable over it, said discs having each a pluralityof transmission points for detachable connection each to a transmissionmember allotted to a sign-key, which points of one disc are arranged tocommunicate each with a point at the inner ffit'c of the other disc andare so spaced that when one disc is rotated relatively to the other eachtransmission point of one disc will be advanced to the preceding one ofthe other disc, the movable disc having on its periphery teeth spacedapart to correspond to the stepping required for single-step changes ofthe transmission points, a key having a pawl arranged to engage saidteeth in succession and advance" the movable disc one space at a time, aspring'tending to move the movable disc in a direction opposite to thatin which it is advanced by the key, a spring-controlled retaining-pawlfor engaging with said teeth and preventing the return movement of themovable disc after each advance, said retaining-pawl having twopositions in which it can be held by its controlling spring, and a stopcarried by the movable disc and arranged to coact with saidretaining-pawlto move it into its disengaged position when the disc hascompleted a cycle of movement and to again coact with the same to returnit to its teethengaging position -wlien the disc has returned, under theaction of its spring, to its starting position, substantially asdescribed.

25. In a machine of the character described, a code-changing devicecomprising two coaxial discs placed face to face, whereof one is fixedand the other is rotatable over it, said discs having each a pluralityof transmission points-for detachable connection to a transmissionmember allotted to a sign-key, which points of one disc are arranged tocommunicate each with a point at the inner face of the other disc andare so spaced that when one disc is rotated relatively tothe other eachtransmission point of one disc will be advanced to the preced ing one ofthe other disc, the movable disc having on its periphery teeth spacedapart to correspond to the stepping required for single-step changes ofthe transmission points, a key having a pawl arranged to engage saidteeth in succession and advance the movable disc one space at a time, aspring tending to, move the movable disc in a direction opposite to thatin which it is advanced by the key, a Spring-controlled retaining-pawlfor engaging with said teeth and preventing the return movement of themovable disc after each advance, said retaming-pawl having two positionsin which it can be held by its controlling spring, a

stop on the fixed disc for coacting with the said pawl on the key andholding the same taining-pawl, .and a stop carried by the movable discand arranged to coact with said pin to move the retaining-pawl into itsdisengaged position when the disc has completed one'revolution and toagain coact with the pin to return the retaining-pawl to its teethengaging position when the disc returned, under the action of itsspring, to its starting position, substantially as described.

26. In a. machine of the type described, the combination with a set ofcharacterproducing sign-keys, of a code-changing'device comprising twocode-changing members whereof one is movable in relation to the other,said members having each a plurality of transmission ports, one for eachof said keys, which ports of one member are arranged to register withthose of the other and are so spaced that when one member is stepped onespace relatively to the other each port of one member will be advancedto the preceding one of the other member; a plurality of cylinders, onefor each key, a plurality of pistons, onein each cylinder, operativelyconnected each with one of said keys, a pneumatic power-supply duct, aset inder, connected each at one end to one of i of passages, onealloted to each cylinder, connected each to said duct, a group of tubes,one for each cylinder, connected each at one end to one of said ports inone code-changing member and connected each at the other end to one ofsaid passages, and valves associated each with one of said keys andarranged eachto control one of said passages,

substantially as described.

27. In a machine of the type described, the combination with a set ofcharacter-producing sign-keys, of a code changing device comprising twocode-changing members whereof one is movable in relation to the other,said members having each a plurality of transmission ports, one for eachof said keys, which ports of one member are arranged to register withthose of the other and are so spaced that when one member is steppedone" space relatively to the other each port of one member will beadvanced to the preceding one of the other member; a plurality ofcylinders, one for each key, a plurality of pistons, one in eachcylinder, operatively connected each with one of said keys, a pneumaticpower-supply duct, a set of passages, one alloted to each cylinder,connected each to said duct, a second set'of passages, opening each intoone of said cylinders, a group of tubes, one for each .cyl-

said, ports in one code-changing member, and manually-operable meansconnected with the other ends of said tubes, whichcomprising means arearranged to place said tubeseach stantially as described.

28. In a machine of the type described, the combination with a set ofcharacter-producing sign-keys, of a code-changing device twocode-changing members whereof one ismovable in relation to the other,said members having eachaplurality of transmission points, one for eachof said keys, which ports of one member are arranged to register withthose of the other and are so spaced that when one member is stepped onespace relatively to the other each port of one member will be advancedto the preceding one of the other member; a plurality of cylinders, onefor each key, a plurality of pistons, one in each cylinder, operativelyconnected each with one of said keysfir pneumatic power-supply duct, aset of passages, one allotted to each cylinder, connected each tov saidduct, controlling valves constituting each an extension of one of saidpistons and arranged each to control one of said passages, a second setof passages opening each into .one of said cylinders, a group of tubes,one for each cylinder, con-v nected each at one end to one of said portsin one code-changingmember, and manual- -ly operated valves, one at theother end of each of said tubes, for placing the tubes at will intocommunication with either of said sets of passages and closing theirconnection with the other of said sets, substantially as described. a I

29. In a machine of the type described, the combination with a set ofcharacter-producing sign-keys, arranged in rows, of 'a code-changingdevice comprising two codechan ing members, whereof one is movable in reation to the other, said members having each a plurality of transmissionports, one for each of said keys, which ports of one member are arrangedto register with those of the other and are so spaced that when onemember is stepped one space relatively to the other each port of onemember will be advanced to the preceding one of the other member aplurality of cylinders, one for each key, a plurality of pistons, one ineach cylinder, operatively connected each ing in the form' of an endwisemovable tube closed at one end and having'a lateral portforconnectioneach with a passage of both said sets of passages, whichmanually-operatedvalves are arran ed 1n rows corresponding to said rowsof eys, andslidable cam members, one for each row of manuallyoperatedvalves, arranged each to operate all the valves of "one rowsimultaneously, substantially as described.

In testimony whereof I have signed my name to this specification.

SIDNEY HOLE.

